Table 3. Meta-analysis of association between SMAD3 rs12901499 polymorphism and OA.

Comparison	OR (95%CI)	P-value	P for heterogeneity	I2 (%)	Model
G vs A	1.26(1.12, 1.42)	<0.001	<0.001	75.8	Random
GG vs AA	1.39(1.15, 1.67)	0.001	0.011	56.2	Random
GG + GA vs AA	1.34(1.07, 1.68)	0.010	<0.001	79.9	Random
GG vs GA + AA	1.32(1.11, 1.56)	0.001	<0.001	71.6	Random
GA vs AA	1.25(0.96, 1.63)	0.101	<0.001	84.0	Random